Dismounted Cavalry?

[Sp4]

They make bad infantry and yes, the main problem is the unit size. Might work against light infantry (archers and such) but otherwise no. I never dismount anything and never use dismounted units except for the naval landings, where you end up with a dismounted general (although sometimes, I'll swap the general for a different one before the battle and put him in some kind of heavy infantry unit)

[Slaists]

If the unit info cards can be trusted, dismounted cavalry retain their extra hit-points. For example, dismounted elephant riders show up with 700+ hps.